Yup. Truth is, that's all you really need to look at. Just establish a baseline that your total T levels can't exceed X amount. If they do, have them take a more advanced screening to see if that is just normal for that person. There are some dudes walking around with very high levels of test, naturally. However if you're rocking out 1800-1900 for total T you're using something.

I don't know this is physiologically possible, but I know a guy that was getting Dr prescribed test cyp and taking 300-400mg per week and was still testing at like 350-400. They had no explanation of where the hell it was going.